Hypodermic syringe.



No. 723,588. PATENTED MAR. 24, 1903. F.- S. DICKINSON.

HYPODERMIG SYRINGE.

- APPLICATION FILED JAN.'15, 1901.

no monnn.

ATTOHN UNITED STATES PATENT Genres,

FAIRLEIGH S. DICKINSON, OF BAYONNE, NEW JERSEY.

HYPODERMIC SYRINGE.

SPECIFICATION forming part of. Letters Patent No. 723,588, dated March 24, 1903. Application filed January 15, 190]. Serial No. 43,324. 2N0 modem 1'0 ail whom it may concern-.- Be it known that I, FAIRLEIGH S. DICKIN- SON, a citizen of the United States, and a resident of Bayonne, in the county of Hudson and State of New Jersey, have invented a new and Improved'Hypodermic Syringe, of which the following is a full,clear,and exact description. The purpose of the'invention is to provide a hypodermic syringe with a glass barrel and means whereby a metal plunger or piston can be used with perfect satisfaction without packing or washers of any description.

A further purpose of the invention is to provide the body of the syringe with a tip so constructed that a special form of needlehub may be used without washers and so that the said tip when used with a washer will neatly receive the conventional needle-hub.

The invention consists in the novel construction and combination of the several parts, as will be hereinafter fully set forth, and pointed out in the claim.

Reference is to be had to the accompanying drawings, forminga part of this specification, in which similar characters of reference indicate corresponding parts in all the figures.

Figure 1 is a longitudinal section through a hypodermic syringe constructed in accordance with my invention. Fig. 2 is an enlarged longitudinal section through a needlehub especially adapted for with the syringe. Fig, 3 is an enlarged section through the outer cap for the barrel, illustrating the tip carried thereby in side elevation; and Fig. 4 is an enlarged longitudinal section through a part of the glass barrel.

A represents the glass barrel, which is open at both of its ends. barrel A is closed by a cap 10, preferably made of metal, which cap is secured to the exterior of the barrel in any suitable or approved manner and may be removable from the barrel. This cap is provided with a tip 11, adapted to receive the hub of a needle. The tip 11 and the cap are provided with a longitudinal channel 12, through which liquid may escape. At that portion of the tip 11 adjacent to the cap an exterior thread 13 is produced, and this thread is a standard thread. The tip extends beyond this threaded portion, and this outer end 1i of the tip is plain use in connection- The outer end of the section 14 of the tip will engage with the walls of the conical chamber 17 of the hub, and at the inner end of the hub-chamber a thread 18 is formed, adapted to receive the thread 13 on the tip 11. When the hub 15 is placed upon the tip and has been screwed to place, a space intervenes between the inner end of the hub and opposing outer face of the cap, as shown in Fig. 1, and a space 19 also intervenes between the outer end of the tip and opposing wall of the chamber in the hub, While the tapering portion 14 of the tip is in close engagement with the tapering walls of the hub-chamber. Thus it will be observed that as the threads wear constantly by placing the hub in position on the tip there is ample room to compensate for wear, as a long time will elapse before the needle-hub will be brought in engagement with the cap and the end of the tip in engagement with the corresponding wall of the hub-chamber. It will also be observed that a liquid and air tight connection is thus effected between the tip and the needle-hub.

At the opposite end of the barrel A a collar20 is secured, and a sleeve 21 is preferably made integral with this collar, the sleeve or the collar being provided with the usual fingergrip 22. A metal plunger 24 of one diameter throughoutits length is adapted to slide freely in the barrel A and snugly in a bore or channel 23, produced in the sleeve and collar, the said bore or channel 23 being truly reamed out and of the same diameter throughout its length. Theouterfaceofthepistonorplunger 24 is likewise truly turned or finished and the diameter of the bore or channel 23 in the collar and sleeve 20 and 21 is infinitesimally greater than the diameter of the piston.

Under this construction nopackingor washers are necessary, as when the needleis closed or the outer end of the barrel is closedwvhen the piston is operated a vacuum will be produced in the barrel, and when a syringe constructed as set forth is operated none of the liquid will escape at the sleeve 21.

I desire it to be understood that the im proved form of needle-hub may be used with a washer upon the usual type of syringe.

Having thus described my invention, I claim as new and desire to secure by Letters Patent- A hypodermic syringe, consisting of a glass barrel, a collar secured upon one end of the barrel and provided with an integral and outwardly-projecting tapering sleeve, the collar and sleeve being provided with a bore of a uniform diameter, and the collar with a fin ger-piece, a cap secured on the other end of the barrel and provided with a tip having a threaded cylindrical portion and a plain conical portion beyond the threaded port-ion, a needle-carrying hub provided with a chamber having a plain conical inner portion and a cylindrical threaded outer portion screwing on the threaded portion of the tip, and a metal plunger uniform in diameter throughout its length and fitting air and water tight in the bore of the collar and sleeve, substantially as herein shown and described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing Witnesses.

FAIRLEIGI-I S. DICKINSON.

Witnesses:

J. FRED. ACKER, EVERARD BOLTON MARSHALL. 

